You'll need to walk the deep structure of all element declarations
(including their anonymous complex types), all complex type definitions
(in particular their particle contents and of course recursively the
anonymous complex types of the element declarations), and all model
group definitions (in particular, the model group's contents).

You'll need to walk the deep structure of all element declarations
(including their anonymous complex types), all complex type definitions
(in particular their particle contents and of course recursively the
anonymous complex types of the element declarations), and all model
group definitions (in particular, the model group's contents).